The hashtag is the new language of 2013. It derived first from Twitter when Chris Messina (internet geek) proposed the idea of it with the hashtag "barcamp" as something he thought it would be similar to.
It worked. After that, hashtags were a thing on Twitter. They thought it was a good idea, and so did everyone else. There's not really another source of the hashtag, except for a typo somewhere on the internet before, but Twitter made it #official. It's even in the dictionary, look it up. It also doesn't come up as a misspelling anywhere like a word document, or at least some. Hashtags got cool, fast. There's not an alternative hashtag for people who prefer something like % or ^ because that's just dumb. Hashtags also help people find what they're looking for too. It's not just a tag or comment at the end of a joke. It's to find topics, tweets or articles, making life easier; that's the point (for the one's who are unaware of this). #realtalkAccording to many social media sites, the most popular hashtag on Instagram is "love". It's pretty common, nothing out of the ordinary, but there are other hashtags that don't make too much sense like #jj and #a.
As for now, hashtags are here to stay. #forever
